Means for limiting amplitude adjustment of the zigzag mechanism for sewing machines



June 18, "1963 w. D. SZUBA ETAL 3,094,035

' MEANS FOR LIMITING AMPLITUDE ADJUSTMENT OF THE ZIGZAG MECHANLSM FOR SEWING MACHINES Filed Spt. 26; 1960 Fig. 4.

2 INVENTORS.

WALTER 0. 5202A and JACOB M. BENZ/N6 KIWI United States Patent 3,094,085 MEANS FOR LIMITING AlVIPLITUDE ADJUST- MENT OF THE ZIGZAG MECHANISM FOR SEW- lNG MACHINES The present invention relates to means for limiting the ampiltude adjustment of the zigzag mechanism for sewing machines.

A sewing machine has heretofore been provided with adjustable stops for limiting the manual adjustment of the zigzag amplitude mechanism between desired maximum and minimum positions to facilitate shifting between a wide and a narrow stitch pattern. The object of this invention is to provide such stops which are simple and economical, easy to operate and dependable in that they will always effectively limit the adjustment of the zigzag amplitude to a preselected position.

Briefly this invention relates to a pair of stops for amplitude adjusting of a manually controlled zigzag sewing machine. The stops are carried individually by two levers pivoted on a common axis and are adapted to be engaged by the knob or other means movable with the amplitude adjusting shaft, there-by limiting turning of the shaft to selected maximum and minimum positions. The two levers are each adapted to be locked in selected position by a single clamping element or thumb screw, the levers for this purpose being provided with overlapping arcuate edge portions or slots concentric with the pivot axis of the lever, which arcuate edge portions or slots are adapted to cooperate with the clamping element.

Having in mind the above and other objects that will be evident from an understanding of this disclosure, the invention comprises the devices, combinations and arrangements of parts as illustrated in the presently preferred embodiment of the invention which is hereinafter set forth in such detail as to enable those skilled in the art readily to understand the function, operation, construction and advantages of it when read in conjunction with the accompanying drawings in which:

FIG. 1 is a fragmentary elevational view of a sewing machine embodying the present invention.

FIG. 2 is a fragmentary vertical sectional view taken substantially on the line 22 of FIG. 1.

FIG. 3 is a fragmentary horizontal sectional view taken substantially 0n the line 3-3 of FIG. 1.

FIG. 4 is a fragmentary vertical sectional view taken substantially on the line 4-4 of FIG. 3.

With reference to the drawings there is illustrated a fragmentary portion of the frame of a zigzag sewing machine, including a standard 1 from the upper end of which extends the bracket arm 2.

The illustrated machine includes a zigzag mechanism for effecting movement of the needle laterally of the line of feed of the machine to define a zigzag or ornamental stitch pattern, and having a control shaft 3 extending through the wall of the bracket arm 2 for effecting amplitude adjustments of the zigzag mechanism upon turning the control shaft 3. The control shaft 3 is adapted to turn manually by the operator by means of a handle or knob 4 loosely mounted upon the control shaft 3 for endwise sliding and coupled to the control shaft 3 for unitary turning by means of a stud 5 carried by the knob 4 at a point spaced radially from the control shaft 3 and extending therefrom in a direction parallel to the axis of the control shaft 3. The stud 5 extends through a slot 6 in a flange 7 integral with a sleeve 8 mounted on the control shaft 3 and secured thereto by a pin 9.

Patented June 18, 1963 To indicate the amplitude setting of the zigzag mechanism, the flange 7 is provided with markings such as a pointer 10 that cooperates with indicia 11 on a cover plate 12 that is secured to and held in spaced relation relative to the bracket arm 2 by screws 13 which extend through sleeves 14.

The sleeve 8 is provided at its end adjacent to the wall of the bracket arm 2 with a reduced diameter portion 15 on which are pivotally mounted a pair of levers 16 and 17. The levers 16 and 17 are isolated from each other, so that one may be adjusted without affecting the adjustment of the other, by a pair of washers 18 disposed one between the levers 16 and 17 and one between the lever 16 and the shoulder formed by the reduced diameter portion 15, the washers having laterally bent cars 19 entering apertures 20 in the wall of the bracket arm 2. The levers 16 and 17 extend laterally from the pivot axis thereof outwardly through a slot 21 in the cover plate 12 with the free ends thereof provided with knobs 22 disposed at a position conveniently available for manually shifting said levers pivotally.

Each of the levers 16 and 17 is provided with an arm 23 extending laterally relatively to said lever and into the path of motion of the stud 5 to be engaged by and thus serve as a stop for the stud 5. The arm 23 is disposed upon opposite sides of the stud 5 and thus limits turning of the knob 4- in opposite directions, the arm 23 on the lever 16 defining the minimum position stop while the arm 23 on the lever 17 defines the maximum stop.

For securing the levers 16 and 17 in adjusted position, there is provided in each an arcuate slot 24 coaxial of the pivot axis of the levers, which is the axis of the control shaft 3. The slots 24 are formed in an enlarged intermediate portion of the levers and are both of the same radius relative to the pivot axis of the levers. A fastening screw 25 has a shank 26 that extends through both of the slots 24 and is threaded into the wall of the bracket arm 2 and has a head 27 that overlies the edge portions of the outermost lever 16 adjacent to the slot. A spacing sleeve 28 is mounted on the shank 26 between the levers 1'6 and 17 to isolate the levers so that the pivotal movement of one will not disturb the pivotal setting of the other. Thus, when the screw 25 is turned down, the head 27 thereof will clamp the lever 16 against spacing sleeve 28 and it in turn will clamp the lever 17 against the wall of the bracket arm 2, thereby releasably securing the levers 16 and 17 in their adjusted position. Indicia 29 is provided on the cover plate 12- to indicate the setting of the stops.

The knob 4 is normally biased outwardly endwise of the control shaft 3' by a coil compression spring 30 surrounding the control shaft 3 in an annual space 31 provided by counterboring the hole in the knob that receives the control shaft 3-, and acting between the bottom of the hole and the end of the sleeve 8. A sleeve 32 is freely mounted for turning on the end of the control shaft 3 and is held thereon by a screw 33. The sleeve 32 limits the outward movement of the knob 4 under the action of the spring 30. The sleeve 32 is provided with a V-shaped diametrically arranged deep groove 34 and a similar shallow groove 35 disposed at a right angle thereto. The grooves 34 and 35 are adapted to receive a complemental raised lug 36 on the face of the knob 4-. When the sleeve 32 is turned to seat the lug 36 in the groove 34, the knob 4 moves outwardly on the control shaft 3 to move the stud endwise out of cooperation with the arms 23 of the levers 16 and 17. This provides for normal operation of the zigzag amplitude adjustment mechanism. When the sleeve 32 is turned relatively to the knob 4 to seat the lug 36 in the shallow groove 35, as illustrated in FIGS. 2 and 3, the knob 4 is held in on the control shaft 3' with the stud 5 disposed between and in operative engagement with the arms 23 of the levers 16 and 17, thus rendering the arms 23 effective as stops for limiting the turning of the knob 4.

Numerous alterations of the structure herein disclosed will suggest themselves to those skilled in the art. However, it is to be understood that the present disclosure relates to a preferred embodiment of our invention which is for the purpose of illustration only and not to be construed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims.

Having thus set forth the nature of this invention, what we claim herein is:

1. In a zigzag sewing machine having a frame and a zigzag amplitude adjustment mechanism including a control shaft to effect adjustment of the zigzag amplitude upon turning thereof, a manually actuated knob secured to said control shaft for unitary turning, means for limiting turning of said control shaft to a maximum and minimum zigzag amplitude setting comprising a pair of levers, means for mounting both of said levers on said frame for pivotal movement about a common axis and in planes normal to the axis of said control shaft, said levers having free ends accessible for manually effecting pivotal movement thereof, means carried by said knob and disposed between and adapted to engage said levers upon turning said knob thereby to limit adjustment of said control shaft, said levers having overlapping arcuate edge portions concentric with the pivot axis of said levers, and threaded means carried by said frame adjacent to said arcuate edge portions at a point where said edge portions overlap and having a head overlying said overlapping edge portions for simultaneously clamping both of said levers against pivotal movement when said threaded means is turned down.

2. In a zigzag sewing machine having a frame and a zigzag amplitude adjustment mechanism including a control shaft to effect adjustment of the zigzag amplitude upon turning thereof, a manually actuated knob secured to said control shaft for unitary turning, means for limiting turning of said control shaft to a minimum and maximum zigzag amplitude setting comprising a pair of levers, means for mounting both of said levers on said frame for pivotal movement about a common axis and in planes normal to the axis of said control shaft, said levers having free ends accessible for manually effecting pivotal movement thereof, an arm carried by each of said levers and extending laterally therefrom, a stud carried by said knob and disposed between and adapted to engage said arms upon turning said knob thereby to limit adjustment of said control shaft, each of said levers having an arcuate slot concentric with the pivot axis of said lever, said slots having the same radius, a screw having a shank extending through said slots and threaded into said frame and a head overlying the edge portion of said levers adjacent to said slots for simultaneously clamping both of said levers against pivotal movement when said screw is turned down.

3. In a zigzag sewing machine having a frame and a zigzag amplitude adjustment mechanism including a control shaft to effect adjustment of the zigzag amplitude upon turning thereof, a manually actuated knob secured to said control shaft for unitary turning, means for limiting turning of said control shaft to a maximum and minimum zigzag amplitude setting comprising a pair of levers pivotally mounted on said control shaft and having free ends accessible for manually effecting pivotal movement thereof, an arm carried by each of said levers and extending laterally therefrom, a stud carried by said knob and disposed between and adapted to engage said arms upon turning said knob thereby to limit adjustment of said control shaft, said levers having overlapping arcuate edge portions concentric with said control shaft, and threaded means carried by said frame adjacent to said arcuate edge portions at a point where said edge portions overlap and having a head overlying said overlapping edge portions for simultaneously clamping both of said levers against pivotal movement when said threaded means is turned down.

4. In a zigzag sewing machine having a frame and a zigzag amplitude adjustment mechanism including a control shaft to effect adjustment of the zigzag amplitude upon turning thereof, a manually actuated knob secured to said control shaft for unitary turning means for limiting turning of said control Shaft to a maximum and minimum zigzag amplitude setting comprising a pair of levers pivotally mounted on said control shaft and having free ends accessible for manually effecting pivotal movement thereof, washers disposed on said control shaft between said levers and between said levers and said control shaft and means for securing said washers against turning relatively to said frame with said levers and control shaft, an arm carried by each of said levers and extending laterally therefrom, a stud carried by said knob and disposed between and adapted to engage said arms upon turning said knob thereby to limit adjustment of said control shaft, said levers having overlapping arcuate edge portions concentric with said control shaft, and threaded means carried by said frame adjacent to said arcuate edge portions at a point where said edge portions overlap and having a head overlying said overlapping edge portions for simultaneously clamping both of said levers against pivotal movement When said threaded means is turned down.

References Cited in the file of this patent UNITED STATES PATENTS 1,797,737 Tenney Mar. 24, 1931 2,014,916 Tieslcr Sept. 17, 1935 2,887,967 Kasper et a1. May 26, 1959 2,929,344 Theenhausen et al. Mar. 22, 1960 2,971,397 Bunting Feb. 14, 1961 FOREIGN PATENTS 148,924 Australia Nov. 5, 1952 

1. IN A ZIGZAG SEWING MACHINE HAVING A FRAME AND A ZIGZAG AMPLITUDE ADJUSTMENT MECHANISM INCLUDING A CONTROL SHAFT TO EFFECT ADJUSTMENT OF THE ZIGZAG AMPLITUDE UPON TURNING THEREOF, A MANUALLY ACTUATED KNOB SECURED TO SAID CONTROL SHAFT FOR UNITARY TURNING, MEANS FOR LIMITING TURNING OF SAID CONTROL SHAFT TO A MAXIMUM AND MINIMUM ZIGZAG AMPLITUDE SETTING COMPRISING A PAIR OF LEVERS, MEANS FOR MOUNTING BOTH OF SAID LEVERS ON SAID FRAME FOR PIVOTAL MOVEMENT ABOUT A COMMON AXIS AND IN PLANES NORMAL TO THE AXIS OF SAID CONTROL SHAFT, SAID LEVERS HAVING FREE ENDS ACCESSIBLE FOR MANUALLY EFFECTING PIVOTAL MOVEMENT THEREOF, MEANS CARRIED BY SAID KNOB AND DISPOSED BETWEEN AND ADAPTED TO ENGAGE SAID LEVERS UPON TURNING SAID KNOB THEREBY TO LIMIT ADJUSTMENT OF SAID CONTROL SHAFT, SAID LEVERS HAVING OVERLAPPING ARCUATE EDGE PORTIONS CONCENTRIC WITH THE PIVOT AXIS OF SAID LEVERS, AND THREADED MEANS CARRIED BY SAID FRAME ADJACENT TO SAID ARCUATE EDGE PORTIONS AT A POINT WHERE SAID EDGE PORTIONS OVERLAP AND HAVING A HEAD OVERLYING SAID OVERLAPPING EDGE PORTIONS FOR SIMULTANEOUSLY CLAMPING BOTH OF SAID LEVERS AGAINST PIVOTAL MOVEMENT WHEN SAID THREADED MEANS IS TURNED DOWN. 